366 



It will be observed how very nearly the velocity, as determined 

 by the formula u= ^, coincides with the velocity found by ex- 

 periment. Hence we conclude that the velocity of ascent of the 

 liquid through the absorbent varies inversely as the space. 



The relation between T and S may be generally expressed by 

 the formula 



T=«(S+/8)«- ft (1) 



where a, /8, and p are constants. 



By differentiation, we get 



dS_ 1_ 



but 



dS 



dT- 



1 



'• ™**(S + /3) ; (2) 



and when /8=0, or is very small, as in the foregoing experiment, 

 we have 



1 



v= 



2aS' 



From equations (1) and (2) we get 

 S-f/3 



(3) 



(4) 



